Time dependent CP-violation phenomena are a powerful tool to precisely measure fundamental parameters of the Standard Model and search for New Physics. The Belle II experiment is a substantial upgrade of the Belle detector and will operate at the SuperKEKB energy-asymmetric e+e- collider. The design luminosity of SuperKEKB is 8 x 10^35 cm^-2 s^-1 and the Belle II experiment aims to record 50 ab^-1} of data, a factor of 50 more than the Belle experiment. This dataset will greatly improve the present knowledge, particularly on the CKM angles phi_1/beta and phi_2/alpha by measuring a wide spectrum of B-meson decays, including many with neutral particles in the final state. A study for the time-dependent analysis of B0 -> pi0pi0, relevant for the measurement of phi_2/alpha, and feasible only in the clean environment of an e+e- collider, will also be given.